#include <stdio.h>
 int Sum(int s, int e)
 {
 int result = 0;
 int i = s;
 for(; i <= e; i++)
 {
 result += i;
 }
 return result;
 }
 int main()
 {
 int start = 1;
 int end = 100;
 printf("I will begin\n");
 int n = Sum(start, end);
 printf("running done, result is: [%d-%d]=%d\n", start, end, n);
 return 0;
 }
